Hammer means for a rotatable mixing drum



March 12, 1957 P. s. HETEJI 2,784,952

HAMMER MEANS FOR A ROTATABLE MIXING DRUM Filed Dec. 27, 1955 FIG. 2

PAUL S. HETEJI IN V EN TOR.

Mad/ 1 M United States Pa e p HAMMER MEANS FOR A ROTATABLE MIXING DRUM Paul S. Heteji, North Plainfield, N. 3., assignor to Worthington Corporation, Harrison, N. 1., a, corporation of Delaware Application December 27, 1955, SerialNo. 555,350 5 Claims. (Cl. 25--175) The present invention relates to a rotatable mixing drum and more particularly to a hammering device for said drum.

in a mixing drum for example, a concrete mixing drum wherein materials are inserted therein to be mixed and the drum is rotated, the material sometimes clings or adheres to the inner periphery of the drum. When the drum has been in use over a long period of time, the drum must be placed out of operation due to the necessity of removing or cleaning the material therefrom.

.lnaccordance with the present invention, a hammer device is provided for continuously striking a series of blows against the outer surface of the drum wall to prevent material being mixed therein from adhering or clinging to the inner surface of the drum wall to thereby eliminate the need for removing the drum from service periodically in order to remove material therefrom.

The present invention further provides a hammering device for a rotatable mixing drum having control means for engaging and disengaging the operation of the device when desired without stopping the rotation of the drum.

The present invention further provides a hammering device for a mixing drum having a plurality of hammer means which strike a series of blows against the drum, which hammer means upon starting. in operation are not engaged at exactly the same instant and thereby reduce the starting inertia load required to place them in operation.

The present invention further provides a hammering device for. a rotatable drum wherein hammer means are hinged on rotatable carriers to utilize the force of: gravity as well as the rotatable speed of the carriers to cause their impact.

The hammering device of the present invention comprises a plurality of rotatable hammer means disposed on a rotatable shaft driven from the gear ring of the rotatable mixing drum, and clutch means for engaging and disengaging the hammer means from rotation, and control means for actuating the clutch means.

The present invention further provides a hammering device for a rotatable drum which allows each hammer to strike the periphery of. the drum in approximately as many places as there are teeth on the drum gear ring thus distributing the wear toa maximum about the drum periphery.

The invention will be better understood from the following description when considered in connection with the accompanying drawingshowing a hammering device of the present invention and in which:

Figure l is a diagrammatic view showing a hammering device of the present invention in use with a rotatable concrete mixing drum.

Figure 2, is an enlarged fragmentary view, partly in section, of the hammering device shown in Figure l, and

Figure 3 is a transverse section taken on lines 3-3 of Figure 2.

Referring to the drawings, the reference numeral designates a rotatable concrete mixing drum, supported 2,784,952 Patented Mar. 12, 1957 on rollers 11 fixed on a base 12, and having a gear ring 14 thereon driven by gear means 15 connected to the drum driving means 16.

Referring to Figure 2, the reference numeral 1% gen erally designates the hammering device of the present invention supported for rotation in spaced bearings 19 bolted to transversely extending horizontal beams, of which, one beam 21, is. shown. The longitudinally extending beams are connected by means not shown, to the rotatable drum base 12 for supporting the hammering device thereon.

Hammering device 18 is provided with a longitudinally extending hollow rotatable shaft 23 supported in the bearings 19; A gear wheel 24 is keyed on the shaft between the bearings and. adapted to mesh with gear ring 14 of the rotatable drum to be driven thereby.

Hammer means 25 are arranged on opposite ends of shaft 23 for axial movement thereon and comprise radially extending arms 26 having a counterweight or balance 27 disposed on one end thereof, and a weighted hammer 28 on the other end thereof adapted to strike a series of blows against the outer periphery or surface of the mixing drum it) when the arms and hammers are rotated, as hereinafter described. The hammers 23 are pivotally connected by pins 2% to the hammer arms 26 and are. annularly displaced from one another on shaft 23 so as to strike the surface of the drum alternately to prevent material in the drum from adhering to the inner surface of the drum wall. Hingedly connecting the hammers to the hammer arms permits the force of gravity, as well as the rotational speed of the shaft, to aid in the impact blow against the drum wall and also permits the harnmers to pass the drum after the impact. Each end of shaft 23 is provided with a clutch plate 31? threaded or welded thereto for rotation with the shaft. Clutch plates 36) are provided with inwardly extending teeth or lugs 31 adapted to extend into recesses 32 disposed in the complementary clutch plates 33 welded to the outer side of hammer arms 26 adjacent plates 3%. Compression springs 34 are disposed on shaft 23 between the bearing 19 and, hammer arm 26 adjacent thereto to normally urge a clutch plate 33 into engagement with a clutch plate 39 adjacent thereto to rotate the hammer means 25 when shaft 23is rotated.

A control mechanism 36 is provided for controlling the starting and stopping of the hammering device independently of the rotation of the mixing drum. Mechanism 36 comprises a cylindrical housing 3%, opened at the inner end thereof and adapted to fit loosely over a set of clutch plates 39 and 33 on one end of shaft 23, and a similar housing 42, adapted to fit over the clutch plate set on the opposite end of the shaft. A sleeve 4-1 is connected to housing 42 adjacent an axial opening disposed therein on the outer end of the housing. Sleeve it .in turn is con nected to anannular ring 42. A control rod 37 extends through ring 42, sleeve 41, housing 42, and shaft 23 and is fixedly connected by welding to housin 39 for moving housing 39 axially of shaft 23 into engagement with the hammer arm 26 there adjacent. The end of control rod 37 adjacent ring 40 is pivotally connected to a control link or rod 43. Rod 43 in turn is pivotally connected to the inner end of an inverted L-shaped actuating bracket 44. Ring ltiis pivotally connected to a link or red 45 having the other end thereof pivotally connected to the lower end of the L-shaped. bracket 44. An operating handle 46 is disposed on bracket 44 for irning or rotating the bracket to control the starting and stopping of the hammer device as hereinafter described. The bracket is supported by means not shown.

In operation, when mixing drum 10 is rotated by driving means 16 gear ring 14 disposed thereon meshes with gear wheel 24 and causes shaft 23 to rotate in bearings 19. Compression springs 34 arranged on shaft 23 between bearings 19 and the inner side of hammer arms 25 forces the hammer arms and the clutch plates 33 fixed to the hammers into engagement with clutch plates fixed on opposite ends of shaft 23 so to cause the hammer arms and hammers 28 pivotaliy connected thereto to rotate with the shaft. As the hammers 2? rotate, centrifugal force as well as gravity throws them against the outer surface of mixing drum 1%} and causes them to strike the outer surface of the drum to knock off any material within the drum that may adhere or cling to the inner surface therein. Since the hammers are displaced angularly from one another they strike the drum surface alternately and thus provide a series of continuous blows against the drum surface to prevent any material from adhering thereto.

When it is desired to prevent rotation of the hammers while the drum is still rotating, the control mechanism handle 4-6 is turned or rotated clockwise to the position shown in dotted lines in Figure 2. Looking at Figure 2, this causes link and housing 42 connected thereto to move to the left, so that the inner edge of housing 42 engages the outer side of the hammer arm 26 adjacent thereto and moves it to the left, to the position indicated by the dotted lines adjacent hammer 26 to thus compress spring 34 and disengage the clutch plates from one another and stop the hammer from rotating.

Simultaneously, with this movement of link 45 and housing 42, link 43 and control rod 37 are moved to the right, as shown in dotted lines in Figure 2, thus moving housing 39 connected to rod 37 into engagement with the hammer arm 26 adjacent thereto to compress spring 34 and disengage the adjacent clutch plates from one another to stop rotation of the hammer arm and hammer adjacent thereto.

When it is desired to permit the rotation of the hammers again, the control mechanism handle 46 is moved from its position as shown in dotted lines in Figure 2 to the solid line position therein, causing rod 45 to pull housing 42 to the right, and link 43 and control rod 37 to move housing 39 to the left so that springs 34 force the clutch plates back into engagement with one another to rotate the respective hammer arms and hammers fixed thereto. Thus, the present invention provides a hammering device for striking impact blows against the outer surface of a rotating mixing drum to prevent material from adhering thereto which device may be started and stopped independently of the rotation of the drum.

What is claimed is:

l. In combination, a rotatable mixing drum having a gear ring thereon, and a hammering device for providing a series of impact blows upon the outer surface of said drum, said hammering device comprising a shaft, bearing means for carrying said shaft, gear means fixed on said shaft adapted to mesh with said gear ring for rotating said shaft, swingable hammer means disposed on said shaft adapted to strike impact blows against the outer surface of said drum when rotated, clutch means for detachably connecting said hammer means to said shaft for rotation therewith, said clutch means normally being engaged to cause said hammer means to rotate with said shaft, and control means operatively connected to said clutch means to disengage said clutch means and dis connect said hammer means from said shaft to stop rotation of said hammer means.

2. In combination, a rotatable mixing drum having a gear ring thereon, and a hammering device for providing a series of impact blows upon the outer surface of said drum, said hammering device comprising a shaft, bearing means for carrying said shaft, gear means fixed on said shaft adapted to mesh with said gear ring for rotating said shaft, hammer means slidably disposed on said shaft adapted to strike impact blows against the outer surface of said drum when rotated, said hammer means comprising a plurality of arms each having a hammer pivotally connected to the outer end thereof, said hammers being angularly displaced from one another on said shaft, clutch means for detachably connecting said hammer means to said shaft for rotation therewith, said clutch means normally being engaged to cause said hammer means to rotate with said shaft, and control means operatively connected to said clutch means to disengage said clutch means and disconnect said hammer means from said shaft to stop rotation of said hammer means.

3. The combination of claim 2 wherein said control means comprises a cylindrical housing having linkage means connected thereto adapted to slide said hammer means axially on said shaft.

4. In combination, a rotatable mixing drum having a gear ring and a hammer device for striking a series of impact blows upon the outer surface of said drum, said device comprising a rotatable hollow shaft, bearing means for carrying said shaft, gear means fixed on said shaft adapted to mesh with said gear ring, hammer arms slidably disposed on said shaft, a hammer pivotally connected to the outer end of each arm adapted to strike the outer surface of said drum when rotated, said hammers being angularly displaced from one another on said arms, a first clutch plate with projecting teeth thereon fixed on said shaft adjacent each arm, a second clutch plate fixed on each arm adjacent each said first clutch plate and having recesses therein adapted to recive the teeth of said first clutch plate for connecting each arm to said shaft for rotation therewith, tension means arranged on said shaft adjacent each arm normally urging said clutch plates into engagement with one another to rotate the hammer arms with said shaft, a cylindrical housing disposed adjacent each hammer arm and adapted to slide said adjacent hammer arm axially of. the shaft against the force of said tension means urging said clutch plates into engagement with one another to disengage said clutch plates, and a control rod connected to each housing for moving said housings to disengage the clutch plates from one another and permit relative rotation of said shaft with respect to each hammer arm.

5. In combination, a rotatable mixing drum having a gear ring mounted about the periphery of said drum, and a hammering device comprising a rotatable shaft, bearing means for said shaft, gear means mounted about said shaft between said bearing means, said gear means meshing with gear ring on said rotatable mixing drum, arms slidably mounted on said shaft outwardly of said bearing means perpendicular to the axis of said. shaft, hammer means hingcdly connected to one of the respective ends of said arms adapted to strike impact blows about the periphery of said rotatable drum, clutch means mounted on both ends of said shaft, clutch means mounted on the outer face of said arms, tension means mounted on said shaft between said bearing means and said arms to urge clutch means on face of said arms into engagement with clutch means of said shaft, an actuating housing disposed about both of said clutch means, control means operatively connected to said actuating housing whereby on rotation of said drum said arms will rotate and cause the respective hammer to strike said rotatable drum at intermittent points thereby distributing wear to a maximum about the periphery of said rotatable drum.

References Cited in the file of this patent UNITED STATES PATENTS 655,028 Sneller July 31, 1900 

